Streamlight Protac 2L...it's an excellent and very popular flashlight for EDC.

Cree XR-E LED, 180 lumen high, 10 lumen low, and strobe modes. It pierces the darkness and projects like nobody's business. You don't even feel it with it clipped inside your pocket. It's a great compromise between lumen output and size. You can get them on Amazon.com for around $45 with free shipping.